Noise emissions in wood chipping yards: Options compared.

ABSTRACT

Industrial comminution is becoming increasingly popular, as the result of a growing demand for wood biomass. Such task is performed with either chippers or grinders, which are large, powerful machines, capable of generating much noise. In turn, high noise levels may have negative impacts on the health and comfort of workers, and of the people living in the surroundings of a wood fuel yard. This study gauged the difference between the two main technology options (i.e. chippers and grinders) in order to offer additional decision elements to wood yard planners. The chipper on test generated more noise than the grinder, due to its better ability to process wood and to transmit more energy into it. Since the chipper was equipped with less working tools and turned slower than the grinder, it generated its noise peaks at lower frequency bands. The grinder on test was more suitable for use in wood yards located near settled areas, and was an obvious choice whenever dealing with a diversified and occasionally contaminated raw material stream.